Honing machine



April 2, 1946. 'E. Y. SEYBORG ETAL HONING MACHINE Filed. Dec. 15, 1943 3Sheets-Sheet 3 F6 as NV LNYORG w ,Earnea Patented Apr. 2, 1946 HONINGAomNn Earnest Y. Seborg, Harry J. Caldwell, and Sheldon F. Manning,Rockford, Ill., assignors to Barnes Drill 00., Rockford, 111., acorporation oi Illinois Application December 13, 1943, Serial No.514.066

11 Claims.

The invention relates to honing machines generally .and moreparticularly to improvements inthe tool adjusting mechanism of suchmachines whereby the abrasive elements of the tools are shifted radiallyinto operative engagement with the surface of the work.

It has been found in practice, that accurate control'oi' the rate ofadjustment of the hone, that is, the rate at which the abrasive elementsare moved toward the work surface materially increases theproductiveeiflciency of the tool. More specifically, the loading of theabrasive elements with material removed from thework is substantiallyeliminated, their useful life is increased, and greater precision offinish is attained by regulating the adjustment so as to maintain apredetermined substantially uniform pressure againstthe work surface.The optimum pressure for this purpose varies, of course, with thematerial being operated on, the size of the work, the grade of theabrasive employed and other factors which need not be discussed here.

Control of the adjustment of the abrasive elements of a honing tool hasbeen effected in various ways. One of the most efficient control devicesheretofore available for hone adjustment control purposes utilizes areceding mechanical abutment arranged to restrain the movements of themember which imparts the radial movements to the abrasive elements. Thistype of control provides accurate regulation of the rate of movement ofthe elements and, in addition, prevents excessive movements when softareas in the work are encountered and before the high spots are removedfrom the work surface. While such control devices give generallysatisfactory results'in ordinary honing operations in which theadjustment of the abrasive elements may be effected in comparativelylarge steps and in a relatively short time, they have been foundunsuited for honing operations requiring adjustment of the elements invery small increments over a relatively long period of time.

With the above in view one object of the invention is to provideimproved control mecha nismv for honing tools in which the adjustingmovements of the abrasive elements are restrained by a fluid block orfluid abutment thus retaining the advantageous positive control of themechanical devices but providing greater flexibility as to rates ofadjustment whereby movements of the abrasive elements may be effected insmaller, more uniform increments and more accurately regulated overextended operating periods.

Another object of the invention is to provide in a honing machine animproved mechanism capable of effecting adjustment of the. honin tool atan exceedingly slow yet accurately controlled rate'thereby adapting themachine for certain types of precision finishing requiring relativelylong honing periods.

Still another object is to provide improved control means whereby theinitial adjustment of a honing tool to bring the abrasive elements intooperative engagement with the work may be effected rapidly whileadjustment during actual operation is effected at a much slower rate.

It is also an object of the invention to provide hone adjustingmechanism which is simple and rugged in construction, which is eflicientand reliable in operation, and which is capable of accuratelycontrolling the rate at which the hone is adjusted.

Other objects and advantages or the invention will become apparent fromthe following detailed description of the preferred embodimentillustrated in the accompanying drawingsin which:

Figure 1 is a front elevational view of a honing machine equipped withhone adjusting mechanism embodying the features of the invention.

Fig. 2 is an enlarged side elevational view of the tool supportingheadof the'machine shown in Fig. 1 with parts of the housing broken awayto show details of the tool driving and adjusting mechanism.

Fig. 3 is a sectional view taken in a vertical plane substantially. onthe line 33 of Fig. 2.

Fig. 4 is a sectional view taken in a vertical plane substantially onthe line 44 of Fig. 3.

Fig. 5 is a plan view showing'details of the valve actuating mechanisms.

Fig. 6 is a schematic diagram showing the electrical and hydrauliccircuits of the machine and their relation to the mechanical elements ofthe same.

While the invention is susceptible. of various modifications andalternative constructions, we have shown in the drawings and will hereindescribe in detail thepreferred embodiment, but it is to be understoodthat we do not thereby intend to limit the invention to the specificform disclosed, but intend to cover all modifications and alternativeconstructions falling within the spirit and scope of the invention asexpressed in the appended claims.

By way of illustration, the invention has been shown as embodied in ahoning machine having a tool supporting head In (Fig. 1) mounted forreciprocation on horizontal ways'carried on an elongated bed I l.Reciprocation of the head it ported on an auxiliary bed i rigidlysecured to the end of the main bed opposite the drum i3.

Referring to Fig. 2 of the drawings, the head It comprises a generallyrectangular base l6 having suitable guide means such as rollers I! forcooperation with the ways on the bed ii. Jourasomu I p posed between asuitable abutmentin the spindle l8 and the thrust plate 3| moves theintermediate naled in the base 16 is a hollow spindle l8 arranged toproject at the forward end of the base for connection with a tubulardriver l8 which carries, at its outer end, a honing tool 20. The spindleI 8 is rotatably driven in this instance by a motor Ml through themedium of suitable gearing'enclosed in a housing 2| rigid with the basei8. Thus, in the exemplary machine, the honing tool is continuouslyrotated and simultaneously reciprocated axially of the work. It will beunderstOOd, of course. that the spindle drive mechanism may be arrangedto turn or index the spindle intermittently for straight line honing.

The honing tool 20 herein shown is of the conventional type employed inhoning internal surfaces. In such tools, the abrasive elements are movedradially outwardly from a normal retracted position to engage thesurface of the work. The invention is not limited to use with thisparticular type of tool but may be used to advantage with other types ofhoning tools, as for example the tools designed for honing externalcylindrical surfaces in which the abrasive elements are moved radiallyinwardly from their normal retracted position. In either case. the toolis initially associated with the work with the abrasive elements inretracted position and the elements are adjusted radially into operativeengagement with the work surface, When so adjusted, the tool is rotatedand simultaneously reciprocated axially of the work so as to actuniformly over the entire surface thereof.

As herein shown, the honing tool 20 is adapted to be adjusted by poweroperated means carried on the head and acting through a push rod 22extending axiall through the driver IS. The power means is preferably ofthe pressure fluid actuated type and, as shown in Figs. 2, 4 and 6.comprises a piston 25 working in a cylinder 26 mounted on the base it inaxial alinement with the spindle I8. The cylinder is closed at oppositeends by heads 21 and 28. A piston rod 29, rigidly attached to the piston25, extends through a suitable gland 30 in the front cylinder head 21toward the hollow spindle l8 to abut against a thrust push rod 32rearwardly with the piston thus permitting the abrasive elements of thetool to be returned to retracted position in well-known manner throughthe action of spring means incorporated in the tool.'

In'the exemplary machine, pressure fluid is supplied to the cylinder 26by a pump P (Figs. 2 and 6) driven by a motor M2, both mounted on thebase i8 of the tool supporting head it. The pump P has an intake line 25through which it draws fluid, such as oil, from a sump or reservoir R inthe head. Fluid is delivered under pressure through a pipe 36 to areversing valve V which may be set to direct the fluid by way of pipes31 or 38 to either the rear end or the front end of the cylinder 28while connecting the other end of the cylinder to an exhaustline 39. Theparticular valve illustrated is yieldably held in one position bysuitable spring means and is adapted to be operated to its alternateposition by a solenoid S connected in parallel with the spindle drivingmotor M. The arrangement is such that the valve is set for expanding thetool when the spindle is rotated.

In accordance with the invention, means is provided for metering out thefluid from the forward end of the cylinder 26 to regulate the forwardtravel of the piston 25 and thus control the rate at which the tool 20is adjusted. To this end the forward end of the cylinder is connected tothe pipe 38 through a check valve VI set to allow fluid to pass freelyinto the cylinder but normally preventing discharge of fluid from thecylinder through the pipe 38. The fluid trapped in the front end of thecylinder is thus divertedthrough plate 3| fixed on the end of anintermediate push rod 32 supported and guided for endwise slidingmovement axially of the spindle l8. The push rod 32 is adapted to abutagainst the end of the tool adjusting rod 22 for imparting the movementsof the piston 25 thereto.

To adjust thehoning tool for operation, pressure fluid is introducedinto the rear end of the cylinder 26 thereby moving the piston 25 andthe rods 32 and 22 forwardly on toward'the right as viewed in Fig. 2.The fluid connections are reversed and fluid is introduced into theforward end of the cylinder 26 to return the piston to the 1 rear end ofthe cylinder. Aispring 84 is later a metering device by which the rateof flow may be accurately controlled.

The metering device as herein shown, comprises a reciprocatory member orplunger 40 (Figs. 4 and v 6) reciprocable in a bore 4| formed, in thisinstance, in the side wall of the cylinder 25. The plunger is providedintermediate its ends with a fluid receiving pocket or recess such as aperipheral groove 42 adapted in the reciprocation of the plunger toregister alternately with two ports 43 and 44 which are spaced apartlongitudinally of the bore 4|.

As will be seen by reference to Figs. {and 6 of the drawings, the port43 communicates with the forward end of the cylinder 26 and constitutesan outlet therefor while .the port is connected by a pipe 45 with theexhaust line 39. Accordingly, the groove 42 is periodically filled withfluid forced from the forward end ofthe cylinder 26 by the advance ofthe piston 25 which fluid is discharged through the exhaust port 44. Inthis way small uniform charges of fluid are metered out from thecylinder at regularly spaced intervals thus permitting incrementaladvances of the piston 25 and corresponding incremental movements of theabrasive elements of the honing tool 20. The quantity of fluid permittedto escape from the cylinder in each reciprocation of the plunger 40 isdependent. of course. upon the dimensions of the groove 42. The groovemay be made quite small thus restricting the piston to a very slow rateof advancing movement.

Reciprocation of the plunger 40 may be effected in any suitable manner.In the exemplary apparatus, the plunger is reciprocated by-a lever 46(Figs. 3-6) pivotally secured by a pin 41 to a bracket 48 rigid withthecylinder head 21. One end of the lever 46 is slotted. .as at 48. 'toreceive a flattened section 50 of the plunger 40 formed by recessingopposite sides of the plunger. The

longitudinally disposed slot 52 adapted to receive an eccentric crankpin 53 carried on a hub 54 fast ona shaft 55. The shaft is journaled onthe bracket 48 and may be driven in any preferred manner. As hereinshown, the shaft 55 is driven at a selected rate from the ,pump motor M2through an adjustable speed changer 56 (Figs. 2 and 6) The speed changerhas an outlet shaft 51 fitted with a worm 58 meshing with a worm wheel59 keyed to the shaft 55. In the particular embodiment illustrated, thespeed changer is driven from the motor M2 by a V-belt 50 (Figs. 2 and.6). j

By suitable adjustment of the speed changer 56, the rate ofreciprocation of the plunger 40 and consequently the frequency of thetool adlusting movements of the piston 25 can be regulated for anydesired period of operation. The amplitude of the adjusting incrementsis determined, of course, by the capacity of the fluid recess 42 in theplunger recesses of various capacities will ordinarily be kept onhandand may be quickly and easily placed in service to provide theadjusting increment required for any operation.

At the beginning of an operating cycle the honing tool 20 is associatedin the work with the abrasive elements retracted and the elements musttherefore be shifted a substantial distance to bring them into operativeengagement with the work surface. To avoid loss of time in this initialor preliminary adjustment of the tool, the invention provides novelmeans whereby substantially unrestricted discharge of fluid from thecylinder 26 ahead of the piston 25 is permitted during a predeterminedinitial portion of its forward movement. To this end, provision is madefor operating the valve VI to by-pass the metering device so that thepiston 25 may advance at a rapid rate until the tool is in condition tooperate upon the work justing rate is automatically initiated.

In the exemplary apparatus, the valve VI is a ball type check valvecomprising a tubular casing (Fig. 4) adapted to be screwed into athreaded exhaust port'62 in the front cylinder head 21!. The casing isformed with an internal shoulder 63 defining an exhaust passageencircled by a tapered valve seat facing the cylinder. A movable valvemember 64, herein shown as a ball, is yieldably urged against the valveseat by a spring 65 interposed between the member and a pin 65 extendingtransversely across the casing. The valve member 64 is thereforenormally held in a position to prevent fluid flow from the cylinderthrough the valve while offering relatively.

little resistance to fluid flow into the cylinder.

In accordance with the invention, valve actuating means is provided forshifting the valve member 64 from its seat to open the valve while theinitial adjustment of the honing tool is effected. The valve actuatingmeans, as herein shown, comprises a plunger 61 movable longitudinally ofthe valve casing 6| and having at its inner end a pin 68 engageable withthe valve member 54. The plunger is slidably supported in a gland formedin a plug 69 screwed into the outer end of the valve casing 5|. A springw whereupon the slow metered ad-.

40. Plungers having interposed between the irmer end of the plunger 61and the shoulder .83 in the valve casing urges the plunger outwardly,thus permitting the member 64 to shift forwardly under the action of thespring and close the passage through the valve.

For shifting the plunger 61 to open the valve, a push rod 1| issupported in axial alinement with the plunger and guided for endwisemovement in a suitable'bearing formed in a bracket 12 rigidly secured tothe cylinder head 21. Fixed on the push rod is a collar 13 havingabifurcated arm 14 projecting laterally to straddle a rectangular blockI5 pinned to and reciprocable with the piston rod 29. The block 15 isformed with an upstanding lug 16, into which is threaded an adjustablestop screw 11 adapted to engage the arm 14 and hold the push rod 1| andvalve. actuating plunger 61 in a valve opening position until the pistonhas executed a predetermined portion of its advancing stroke. The screwTl may be readily adjusted to permit the valve VI to close at theinstant the abrasive elements of the honing tool are moved intooperative engagement with the work.

Means is also provided whereby the machine attendant may open the valveVI at any time to effect rapid adjustment of the honing tool. For thispurpose a solenoid SI (Figs. 3, 5 and 6) is mounted at one side of thebracket 12 and its armature 18 is connected by a link 19 with one end ofa lever 80 having its other end pivoted as at ill on the outer end ofthe bracket. The lever 80 1s positionedtc engage the outer end of thepush rod H and to shift the same to valve openin position when thesolenoid is energized. Energization of the solenoid may be controlledthrough the medium of a manually operable switch SW located forconvenient access by the attendant.

It will be apparent from the foregoing that the invention provides honadjusting and control mechanism of a novel and advantageous char acterby which the abrasive elements of a honmg tool may be adjusted through awide range of incremental steps and at a more accurately controlled ratethan has heretofore been practicable. More particularly, the improvedcontrol mechanism permits the abrasive elements of the honing tool to bemoved in exceedingly small increments and at various selected rateswhich may be adjusted to effect relatively slow adjustment of the toolover an extended period. Accurate control of the adjustment rate isobtained by arranging the control mechanism for metering out the fluidtrapped in the forward end of the cylinder of the hone adjustingmechanism in the advancin movement of the piston to adjust the tool. The

metering out is efiected in a manner such that adjustment takes place inincremental steps the frequency of which can be varied as required bythe particular work to be done. In general, the control mechanism issimple andfoolproof in con struction, emcient and reliable in operationand it has a wide range of adjustability that enables it to functionsatisfactorily under substantially any conditions met with in the honingart.

The invention also provides novel means whereby a honing tool may beadjusted rapidly to bring the abrasive elements into operatve engagementwith the work surface preliminary to the actual honing of the surface.loss of time is avoided and the maximum productive capacity of themachine is realized.

We claim as our invention:

1. Adjusting mechanism for honing tools hav- In this Way.

, ing radially shiitable abrasive elements comprising, in combination, amember movable longitudinally to shift the abrasive elements of thetool,

' the forward end of the cylinder, and'means restricting the dischargeof fluid from the forward end of said cylinder to predeterminedincrements released at accurately timed intervals,

and means for varying thelengths the inter vals between successiveincrements to ontrol the rate at which the abrasive elements "of thetool are shifted.

2. Adjusting mechanism for honing tools having radially movable abrasiveelements comprising, in combination, a member shiftable longitudinallyto move the elements of the tool, means ,for shifting said memberincluding a cylinder closed at both ends, a piston reciprocable in saidcylinder and having a piston rod engageable with said member in theforward movement of the piston, means for supplying pressure fluid tothe rear end of said cylinder to move said piston forwardly, said pistonacting in such movement to expel the fluid trapped in the forward end ofthe.

cylinder, and an intermittently operating metering device forrestricting the flow of fluid from the forward end of the cylinder toincrements of predetermined volume, the operating speed of said devicebeing adjustable to regulate the rate at which the tool is adjusted.

3. Adjusting mechanism for honing tools comprising, in-combination, acylinder, a piston in said cylinder, means for supplying fluid to bothends of the cylinder, a port communicating with the forward end of saidcylinder, said piston when driven forwardly by pressure fiuidintroducedinto the rear end of said cylinder-acting to force the fluid in theforward end of the cylinder through saidport, an exhaust port, a plungerhaving a fluid receiving recess, and means for reciprocating saidplunger to present said recess at said ports alternately to receive aquantity of. fluid from said cylinder and to discharge the fluid intosaid exhaust port.

4. Adjusting mechanism for honing tools comprising, in combination, acylinder, a piston reciprocable in said cylinder, means for supplyingfluid under pressure to the cylinder at one side of the piston, anoutlet from said cylinder at the other side ofsaidpiston, said pistonacting to force'fluid from said cylinder through said outlet whenadvancing to adjust a honing tool, and means for controlling thedischarge. of fluid through said outlet to regulate the rate of adsaidport to maintain a relatively slow rate 01 piston movement in adirection efiective to adjust the tool, and means for operating saidvalve to permit a flow of fluid through said fluid connections whereb toincrease the rate of movement of said piston during apredetermined-portion of its advance .in said tool adjusting direction.7

6. Adjusting mechanism for honing tools comprising, in combination, acylinder, a piston reciproc-able in said cylinder, means for supplyingfluid under pressure to said cylinder to force said piston forwardly, apair of outlet ports in said cylinder at the advancing side of saidpiston, valve means operative to prevent the discharge of fluid throughone of said ports, control means for metering the discharge of fluidthrough the other i of said ports, and means actuated by said piston inits reciprocation for operating said valve to permit unrestricteddischarge of fluid therethrough during a predetermined'portion oi thepiston stroke; I

7. Adjusting mechanism for honing tools com-.

prising, in combination, a shiftable member operative to adjust a honingtool, a cylinder, a piston reciprocable in said cylinder, a piston rodfor transmitting the movements of said piston to said member, means forsupplying fluid to each end of the cylinder, a pair of outlet ports insaid cylinder at the advancing side of said piston, valve means normallyclosing one of said ports to the discharge of fluid from said cylinder,means for restricting the discharge of fluid through the other of saidports to control the rate of advance of said piston, an actuating memberoperable to open said valve, and means carried by saidpiston rod adaptedto coact with said actuating member to hold said valve open during apredetermined portion of the piston stroke,

8. Adjusting mechanism for honing tools comprising, in combination, arod shiftable to adjust a honing tool, a cylinder, a piston reciprocablevance of said piston, said controlling means in- 'cluding a memberoperable periodically to permit the passage of a predetermined quantityoi fluid 'through said outlet.

'5. Adjustingmechanism for honing tools comprising, in combination, acylinder closed at both ends, a piston reciprocable in said cylinder,fluid supply connections at both ends of said cylinder, an outlet portat one end of the cylinder, a valve normally operative to prevent thedischarge of fluid from the cylinder through the fluid supply connectionat said one end of the cylinder thereby directing the fluid dischargethrough said port,

means restricting the discharge or fluid through in said cylinder, meansproviding a connection between said piston and said rod, means forsupplying fluid to each end of said cylinder, a pair of outlet ports insaid cylinder at the advancing side of said piston, valve means normallyclosing one of said ports to fluid flow from said cylinder, means forrestricting the flow of fluid from said cylinder from the other of saidports to control the rate of advance of the piston, and means controlledmanually for opening said valve to permit unrestricted discharge offluid from said cylinder through said one port.

9. Adjusting mechanism for honing tools comprising, in combination, arod shiftable to adjust a honing tool, a cylinder, a piston reciprocablein said cylinder, means providing a-connection be-. tween said pistonand said rod, means for supplying fluid to each end oi. said cylinder, apair of outlet ports in said cylinder at the advancing side of saidpiston, valve means normall closing one of said ports to fluid flow fromsaid cylinder, means for restricting the flow of fluid from saidcylinder from the other of said ports to control the rate of advance ofthe piston, a solenoid adapted when energized to open said valve andthereby permit substantially unrestricted discharge of fluid from saidcylinder through said one port, and switch mean for controlling theenergization of said solenoid.v

10. Adjusting mechanism for honing tools having radially movableabrasive elements comprising, in combination, a cylinder closed at bothends, a piston reciprocable in said cylinder, a

pump for supplying fluid under pressure to one end of said cylinder toadvance said piston in a direction effective to move the abrasiveelements of the tool into engagement with a surface to be operated on,said piston acting to force fluid from the other end of said cylinderthrough an outlet port, and means for regulating discharge of fluidthrough said port to control the rate of movement of said piston, saidregulating means including a reciprocator member operative to release apredetermined quantity of fluid from the cylinder in each reciprocatorystroke, and powerv driven means for reciprocating said member.

11. Adjusting mechanism for honing tools comprising, in combination, acylinder closed at both ends, a piston reciprocabie in said cylinder, apump for supplying fluid under pressure to one end of said cylinder toadvance said piston in a direction effective to adjust the honing tool,said piston acting to force fluid from the otherend of said cylinderthrough an. outlet port, a metering device adapted to regulate thedischarge 01 fluid through said port to control the rate of movement ofsaid piston, a motor operative to drive said pump and said meteringdevice, and an adjustable speed changer interposed between said motorand said device.

. EARNEST Y. SEBORG; HARRY J. CALDWELL. SHELDON F. MANNING.

